This invention is directed to a maintenance platform to permit access to the upper region of the furnace of a steam generator. Access to remove slag, or inspect and repair tubes of a superheater extending down from the roof of the furnace is almost always necessary during a scheduled maintenance shutdown of a steam generator, which may occur annually. To presently construct and install a temporary maintenance platform on which workmen can safely reach the superheater area takes time, generally necessitating a lengthy and costly downtime of the steam generator. Also, space requirements outside of the furnace in which to store the platform components and manipulate them during installation within the furnace, is critical.